产耐热蛋白酶乳酸菌的筛选、产酶条件及其酶学性质的研究  

Screening of Thermoduric Proteinase-Producing Lactic Acid Bacteria,Conditions of Enzyme Production and Properties of Produced Thermoduric Proteinase

作　　者：方芳[1] 冀林立[1] 张彦斌[1] 张和平[1] 孟和毕力格[1] 

机构地区：[1]内蒙古农业大学乳品生物技术与工程教育部重点实验室,内蒙古呼和浩特010018

出　　处：《食品科学》2008年第10期375-379,共5页Food Science

基　　金：内蒙古农业大学博士基金项目

摘　　要：从内蒙古部分传统发酵乳样品以及酸菜汤中分离到105株乳酸菌,用检测蛋白酶产生水解圈和福林酚蛋白酶活性测定相结合的方法,从中筛选出一株耐热蛋白酶产生菌株WH29-3-1,该菌株经初步鉴定为Enterococcus faecium。同时,对其产酶条件及酶学性质进行研究。结果表明,菌株WH29-3-1是在以葡萄糖为碳源、蛋白胨+牛肉膏+酵母粉为氮源、碳氮比为0.8、pH7.0的最适产酶培养基中45℃、接种量为4%的条件下发酵培养30h,具有最大产酶量13.13U/ml,且K2HPO4、MgSO4有促进蛋白酶产生的作用。由菌株WH29-3-1产生的耐热蛋白酶的最适作用pH值为7,最适作用温度为50℃。结果表明,该菌是一株具有进一步改造利用价值的产蛋白酶菌株。105 strains of lactic acid bacteria were isolated and identified from dairy products and sour cabbage soup in Bayanhaote fo Inner Mongolia, and a strain producing thermoduric proteinase, named Enterococcusfaecium, was screened from the lactic acid bacteria by detecting hydrolysis circle of proteinase and its activity. The experimental results revealed that the optimal conditions for producing thermoduric proteinase are as follows： glucose as carbon and peptone plus beef extract plus yeast powder as nitrogen sources, carbon-nitrogen ratio 0.8; inoculum size 4%, pH 7.0, fermentation temperature 45 ℃ and fermentation time 30 h. Under these conditions, the yield of thermoduric proteinase is 13.13 U/ml. It was found that K2HPO4 and MgSO4 can promote the production of thermoduric proteinase. The activity of this enzyme is the highest atpH 7 and 50 ℃. Based on the above results, the strain is promising in producing thermophilic proteinase.

关 键 词：乳酸菌 耐热蛋白酶 酶活力 

分 类 号：TS201.3[轻工技术与工程—食品科学]